TY - JOUR A1 - Hentrich, Doreen A1 - Tauer, Klaus A1 - Espanol, Montserrat A1 - Ginebra, Maria-Pau A1 - Taubert, Andreas T1 - EDTA and NTA effectively tune the mineralization of calcium phosphate from bulk aqueous solution JF - Biomimetics N2 - This study describes the effects of nitrilotriacetic acid (NTA) and ethylenediaminotetraacetic acid (EDTA) on themineralization of calciumphosphate from bulk aqueous solution. Mineralization was performed between pH 6 and 9 and with NTA or EDTA concentrations of 0, 5, 10, and 15 mM. X-ray diffraction and infrared spectroscopy show that at low pH, mainly brushite precipitates and at higher pH, mostly hydroxyapatite forms. Both additives alter the morphology of the precipitates. Without additive, brushite precipitates as large plates. With NTA, the morphology changes to an unusual rod-like shape. With EDTA, the edges of the particles are rounded and disk-like particles form. Conductivity and pH measurements suggest that the final products form through several intermediate steps. KW - biomineralization KW - biomimetic mineralization KW - calcium phosphate KW - NTA KW - EDTA KW - precipitation KW - brushite KW - hydroxyapatite Y1 - 2017 U6 - https://doi.org/10.3390/biomimetics2040024 SN - 2313-7673 VL - 2 IS - 4 PB - MDPI CY - Basel ER - TY - JOUR A1 - Hardy, John G. A1 - Torres-Rendon, Jose Guillermo A1 - Leal-Egana, Aldo A1 - Walther, Andreas A1 - Schlaad, Helmut A1 - Coelfen, Helmut A1 - Scheibel, Thomas R. T1 - Biomineralization of Engineered Spider Silk Protein-Based Composite Materials for Bone Tissue Engineering JF - Materials N2 - Materials based on biodegradable polyesters, such as poly(butylene terephthalate) (PBT) or poly(butylene terephthalate-co-poly(alkylene glycol) terephthalate) (PBTAT), have potential application as pro-regenerative scaffolds for bone tissue engineering. Herein, the preparation of films composed of PBT or PBTAT and an engineered spider silk protein, (eADF4(C16)), that displays multiple carboxylic acid moieties capable of binding calcium ions and facilitating their biomineralization with calcium carbonate or calcium phosphate is reported. Human mesenchymal stem cells cultured on films mineralized with calcium phosphate show enhanced levels of alkaline phosphatase activity suggesting that such composites have potential use for bone tissue engineering. KW - spider silk KW - recombinant protein KW - biodegradable polymers KW - biomaterials KW - biomineralization KW - bone tissue engineering Y1 - 2016 U6 - https://doi.org/10.3390/ma9070560 SN - 1996-1944 VL - 9 SP - 93 EP - 108 PB - MDPI CY - Basel ER - TY - JOUR A1 - Taubert, Andreas A1 - Balischewski, Christian A1 - Hentrich, Doreen A1 - Elschner, Thomas A1 - Eidner, Sascha A1 - Günter, Christina A1 - Behrens, Karsten A1 - Heinze, Thomas T1 - Water-Soluble Cellulose Derivatives Are Sustainable Additives for Biomimetic Calcium Phosphate Mineralization JF - Inorganics : open access journal N2 - The effect of cellulose-based polyelectrolytes on biomimetic calcium phosphate mineralization is described. Three cellulose derivatives, a polyanion, a polycation, and a polyzwitterion were used as additives. Scanning electron microscopy, X-ray diffraction, IR and Raman spectroscopy show that, depending on the composition of the starting solution, hydroxyapatite or brushite precipitates form. Infrared and Raman spectroscopy also show that significant amounts of nitrate ions are incorporated in the precipitates. Energy dispersive X-ray spectroscopy shows that the Ca/P ratio varies throughout the samples and resembles that of other bioinspired calcium phosphate hybrid materials. Elemental analysis shows that the carbon (i.e., polymer) contents reach 10% in some samples, clearly illustrating the formation of a true hybrid material. Overall, the data indicate that a higher polymer concentration in the reaction mixture favors the formation of polymer-enriched materials, while lower polymer concentrations or high precursor concentrations favor the formation of products that are closely related to the control samples precipitated in the absence of polymer. The results thus highlight the potential of (water-soluble) cellulose derivatives for the synthesis and design of bioinspired and bio-based hybrid materials. KW - cellulose KW - polyamine KW - polyammonium salt KW - polycarboxylate KW - polyzwitterion KW - calcium phosphate KW - biomineralization KW - brushite KW - hydroyxapatite KW - biomaterial Y1 - 2016 U6 - https://doi.org/10.3390/inorganics4040033 SN - 2304-6740 VL - 4 PB - MDPI CY - Basel ER - TY - JOUR A1 - Salama, Ahmed A1 - Neumann, Mike A1 - Günter, Christina A1 - Taubert, Andreas T1 - Ionic liquid-assisted formation of cellulose/calcium phosphate hybrid materials JF - Beilstein journal of nanotechnology N2 - Cellulose/calcium phosphate hybrid materials were synthesized via an ionic liquid-assisted route. Scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis/differential thermal analysis show that, depending on the reaction conditions, cellulose/hydroxyapatite, cellulose/ chlorapatite, or cellulose/monetite composites form. Preliminary studies with MC3T3-E1 pre-osteoblasts show that the cells proliferate on the hybrid materials suggesting that the ionic liquid-based process yields materials that are potentially useful as scaffolds for regenerative therapies. KW - biomineralization KW - calcium phosphate KW - carbohydrates KW - cellulose KW - hybrid materials KW - ionic liquid Y1 - 2014 U6 - https://doi.org/10.3762/bjnano.5.167 SN - 2190-4286 VL - 5 SP - 1553 EP - 1568 PB - Beilstein-Institut zur Förderung der Chemischen Wissenschaften CY - Frankfurt, Main ER -